Classifying apparatus



Nov. 18, 1958 D. F. HAYS 2,850,776

CLASSIFYING APPARATUS r Filed March 15, 1954 lNVENTOR ATTORNEY United States Patent 2,860,776 CLASSIF-YING APPARATUS Donald F. "Hays, Detroit, "Mich, assignor to-General Motors Corporation, Detrit; Mich., a corporation of Delaware Application March 15, 1954, Serial No. 416,268

9 Claims. 20912) This invention relates to devices for classifyingsolid particles,.and more particularly to sucha devicecapable of separating a mixture of particlesinto-a plurality of sizes, Sizeranges or densities during a singleperiod of operationvof the device.

Many industries are based or atleast dependent upon certain desired properties of different particle sizes of the same material. I In such industries it is necessary to separate 'a powdered material, for instance, into a number of chines in thatlonly one particle size or density could be separated during oneperiod ofioperation of the machine. This required either that the samemachine be loaded and run under particular conditions-to separate eachdesired size 'or density of particleror'that a battery of :machines be available, each to separate particles :of given weight.

It is now proposed to provide a device for 1 classifying solid particles in which both the centrifuge and the gravity separation principles are employed concurrently. The structure of the proposed device is su'ch that a number of particle sizes, size ranges or "densities may be' separated during the same period of operation of a single machine. Furthermore, the structure is such thatthe operation of the device is essentially the same no matterwha'toverall range of particle sizes or densities'is to be classified. The proposed device is also more efiicient than those now used due to the novel arrangement of parts therein for insuring movement of the particles in the proper directions and through the shortest distances.

The proposed device in its preferred form comprises a pair of inverted hollow cones nested in spaced relation and adapted to be rotated as a unit. The outer cone has an open vertex through which particle-laden air is forced so that the air passes upwardly through the space between the cones. Thecones are thenrotatedso thatthe particles are thrown towards the outer cone and forcedalong the conical surface thereof by the component of centrifugal force parallel to such conical surface until such particles may pass through slots in the conical surface. The slots are spaced vertically along the surface of the outer cone, and the above separation'takes place at successively higher slots withdecreasing particle weight.

In-th'e drawings: Figure 1 is a side"elevational'view partly in cross-section of a particle classifying device embodyingutheinven- "'ice tions'of the structure shown by Figures l and .2 and further illustrating the details of internal. construction.

Referring to the drawings in more detail, .a device .10 for classifying particles and embodying the invention comprises means for supplying fluid under pressure such as a blower 12 connected to a particlecontainer 14 by means of a conduit 16. A stationary conduit and support 18 may extend from the container 14 to the particle classifying means 20.

The particle classifying meanst20 comprises -an-inner cone 22, an outer cone 24, and a housing .26, Vertical vanes 28 extend from inner cone=22 to housing 26, form ing passages 30 between theinner cone 22-and the outer cone 24. Vertically spaced horizontalrings 32-extend from outer come 24 to housing 26, intersecting vertical vanes 28and formingchamber 34-therewith Horizontal slots 36 are provided in cone 24 to provide accessto each of the chambers134. The above elements of the classifying means 20 may be formed separately andsecured together or formed integrally so that access may be had to chamber34 and so that'they may be rotated as-a unit by any means such as gears 38 and-40 driven by motor 42. l

A stationary enclosure 44 having vent-46 may beiprovided for classifying means 20, "and this is desirable for the sake of cleanliness and safety.

In operation, a fluid such as air is passed byrneans of b1ower12 through the particle container14,so that the particles maybe agitated thereby and suspended inthe air; The particle-laden' air then passes .throughlconduit 18 to the vertex 37 of inner cone 22. While classifying means Zilis rotated, the particle laden =air isthen passed between cones 22 and 24 through the opening 39. ofcone 24 and upwardlythrough passages 30 =between vanes 28. On entering the rotating :passages 30,th'e particles"are acted upon by cent-rifugal force as Well-as the upward force of the air, which causes theparticles to'be' thrown outwardly against outer cone 24, the heavier particles being thrown outwardly nearer the opening 39' thereof and the lighter particlesfarther away therefrom. It will be noted that the vanes 28 prevent the particles from moving circumferentially with respect to outer cone24 through a distance greater than the distance I between vanes 28.

The component of centrifugal force parallel to the surface of cone 24 will cause the particles thrown against cone 24 to travel upwardly along the surface of cone 24 until they reach one' of the slots 36"at whichtime they will pass through that slot due to the component of-centrifugal force normal tothe cone 24. Thus, all particles forced outwardly to cone 24* below any given slot in one of the passages 30 *will enter the given slot and colle'ctin the chamber34 to which the slot provides access. Thus, the particles will be separatedaccording to weight in the chambers 34, with the heavier particles separating out in the lower chambers. The particles may subsequently be removed from chambers 34 in'anysuitable manner.

The vent 46 may be opened'toany desired degree in order to control the flow of the air through the device '10.

From the foregoing specification and drawings, it'can be seen. thatthere' has been provided a novel device .for

classifying small solid particles 'by which a numberyof sizes or densities ofparticles maybe separated during asingle operation of the device.

What is claimed is:

1. Adevi'ce for classifying. small solid particles, com prising in combination 'fluidimeans' for agitating ,and suspending saidparticles and rotating means for classifying said particles, said classifying means comprising a hollow inverted inner cone, a hollow outer coaxial cone sur rounding said inner cone and disposed in spaced relation thereto, a coaxial cylindrical housing surrounding said '3 outer cone and disposed in spaced relation thereto, said cones and said housing being secured together and adapted to be rotated as a unit, radial vanes extending from the outer surface of said inner cone to the inner surface of said outer cone and thence in the same direction from the outer surface of said outer cone to said housing, said vanes dividing vertically and radially the spaces between said cones and between said outer cone and said housing, vertically spaced horizontal rings extending from said outer cone to said housing, said rings dividing the space between said outer cone and said housing into adjacent horizontal annular chambers, said chambers being divided radially by said vanes, and horizontal slots in said outer cone between said rings providing access of said particles to each of said chambers.

2. A device for classifying small solid particles, comprising in combination fluid means for agitating and suspending said particles and rotating means for classifying said particles, said classifying means comprising a hollow inner cone, a hollow outer coaxial cone surrounding said inner cone and disposed in spaced relation thereto, a coaxial cylindrical housing surrounding said outer cone and disposed in spaced relation thereto, said cones and said housing being secured together and adapted to be rotated as a unit, radial vanes extending from said inner cone to said outer cone and thence in the same direction from said outer cone to said housing, said vanes dividing vertically and radially the spaces between said cones and between said outer cone and said housing, vertically spaced horizontal rings extending from said outer cone to said housing, said rings dividing the space between said outer cone and said housing into adjacent horizontal annular chambers, said chambers being divided radially by said vanes, and openings in said outer cone between said rings and providing access for said particles to each of said chambers.

3. A device for classifying small solid particles, comprising in combination fluid means for agitating and suspending said particles and rotating means for classifying said particles, said classifyng means comprising a hollow inverted inner cone, a hollow outer coaxial cone surrounding said inner cone and disposed in spaced relation thereto, a coaxial cylindrical housing surrounding said outer cone and disposed in spaced relation'thereto, said cones and said housing being secured together and adapted to be rotated as a unit, vertically spaced horizontal rings extending from said outer cone to said housing, said rings dividing the space between said outer cone and said housing into adjacent horizontal annular chambers, and horizontal slots in said outer cone between said rings providing access for said particles to each of said chambers.

4. A device for clasifying small solid particles, comprising in combination fluid means for agitating and suspending said particles and rotating means for classifying said particles, said classifying means comprising a hollow inverted inner cone, a hollow outer coaxial cone surrounding said inner cone and disposed in spaced relation thereto, a coaxial cylindrical housing surrounding said outer cone and disposed in spaced relation thereto, said cones and said housing being secured together and adapted to be rotated as a unit, said outer cone having horizontal slots therein providing access for said particles to said housing, and said housing having means associated with said slots for collecting separately the particles passing through each horizontal row of said slots.

5. A device for classifying small solid particles, comprising in combination fluid means for agitating and suspending said particles and rotating means for classifying said particles, said classifying means comprising a hollow inverted inner cone, a hollow outer coaxial cone surrounding said inner cone and disposed in spaced relation thereto, means surrounding said outer cone for storing classified particles, said cones and said storing means being secured together and adapted to be rotated as a unit, said outer cone having openings therein providing access for said classified particles to said storing means.

6. In a device for classifying small solid particles, the combination of a single pair of telescoped inner and outer conical walls rotatable about the common axis thereof as a unit and defining a conical chamber therebetween, said chamber being disposed obliquely to said axis of rotation of said walls and intersecting said axis at the lower end thereof, said chamber being open at both ends thereof to receive a stream of particle-laden fluid through the bottom end thereof at said axis and to discharge said fluid at the top end thereof, said outer conical wall having a plurality of vertically spaced horizontal slots therein to receive said particles when said chamber is rotated while said particle-laden fluid is passing upwardly therethrough.

7. In a device for classifying small solid particles, the combination of only a single pair of cooperating inner and outer walls rotatable as a unit and defining an annular chamber of increasing diameter, said chamber being disposed obliquely to the vertical axis of rotation of said walls and meeting said axis at the lower end thereof, said passage being open at both ends thereof to receive a stream of particle-laden fluid through the end thereof having the smaller diameter and to discharge said fluid at the end thereof having the larger diameter, said outer wall of said passage having a plurality of vertically spaced openings therein to receive said particles when said passage is rotated while said particle-laden fluid is passing upwardly therethrough.

8. In a device for classifying solid particles, the combination of only a single pair of spaced conical inner and outer walls rotatable as a unit and defining an annular passage therebetween, said passage being disposed obliquely to the vertical axis of rotation thereof and including said axis at one end thereof, said passage being open at both ends thereof to receive a stream of particle-laden fluid through the bottom thereof and to discharge said fluid at the top thereof, said passage being divided by radial walls disposed in the plane of said axis, said outer wall defining said passage having a plurality of vertically spaced horizontal slots therein receiving said particles when said passage is rotated while said particleladen fluid is passing upwardly therethrough.

9. In a device for classifying solid particles, the combination of a single pair of cooperating conical inner and outer walls rotatable as a unit and defining a conical passage therebetween, said passage being disposed obliquely to the vertical axis of rotation thereof and meeting said axis at one end thereof, said passage being open at both ends thereof to receive a stream of particle-laden fluid through the bottom thereof and to discharge said fluid at the top thereof, said passage being divided by radial walls in the plane of said axis, said outer wall defining said passage having a plurality of vertically spaced horizontal slots therein to receive said particles when said passage is rotated while said particle-laden fluid is passing upwardly therethrough.

References Cited in the file of this patent UNITED STATES PATENTS 1,480,685 Ladd Jan. 15, 1924 1,595,259 Stebbins Aug. 10, 1926 FOREIGN PATENTS 241,180 Germany Nov. 27, 1911 

